Phenolic cyanate esters have been described extensively in the art. U.S. Pat. No. 5,360,887, for example, describes a flame resistant thermosetting composition containing a monocyanate ester and a dicyanate ester of the formula ##STR1##
wherein the bridging member A can be a direct bond, methylene or mono- or disubstituted methylene with alkyl and/or an aryl group, or a five or six membered cycolalkylene, sulfonyl, thio, oxyl, carbonyl or xylylene. The teachings in U.S. Pat. No. 5,109,078 represent one of many teachings of cyanato-group containing phenolic resins of the formula: ##STR2##
wherein X is a divalent organic radical, preferably a radical selected from the group consisting of: --CH2--, --CO--, --SO2--, (S)y, ##STR3##
There is a need in the transportation industry, particularly for aircraft interiors, for molded polymeric components that exhibit very low peak heat release rates. Many cyanate esters exhibit good dielectric properties, water absorption and flame retardancy. However, all of the currently known cyanate esters fail to have heat release rates below 35 Joule/g-.degree. K., more preferably below 10 Joule/g-.degree. K. Low peak heat release rates can be attained using other high performance polymers such as polyphenylsulfone, polyamineimides, polybenzoimadazoles and polybenzoxazoles. All of the currently available polymers having relatively low peak heat release rates suffer from one or more disadvantages such as high cost of manufacture or challenging processing requirements. The present invention produces molded articles having the desired low peak heat release rate using cyanate ester compounds and compositions thereof.